INVESTMENT SECURITIES - Schedule of Amortized Cost and Approximate Fair Value of Investment Securities Classified as Available for Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	$ 238,443	$ 219,230
Debt securities, Gross Unrealized Gains	42
Debt securities, Gross Unrealized Losses	(7,738)
Debt securities, Fair Value	230,747	216,722
Equity securities, fair value	1,400
Total, Amortized Cost	238,443	220,077
Total, Gross Unrealized Gains		305
Total, Gross Unrealized Losses		(2,818)
Total, Fair Value	230,747	217,564
Obligations of U.S. government agencies and corporations [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	8,098	8,241
Debt securities, Gross Unrealized Gains	2	8
Debt securities, Gross Unrealized Losses	(232)	(81)
Debt securities, Fair Value	7,868	8,168
Obligations of state and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	35,060	35,572
Debt securities, Gross Unrealized Gains	3	87
Debt securities, Gross Unrealized Losses	(1,102)	(422)
Debt securities, Fair Value	33,961	35,237
Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	16,022	16,428
Debt securities, Gross Unrealized Gains	22	112
Debt securities, Gross Unrealized Losses	(500)	(330)
Debt securities, Fair Value	15,544	16,210
Residential mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	120,778	110,690
Debt securities, Gross Unrealized Gains	11	58
Debt securities, Gross Unrealized Losses	(3,813)	(1,270)
Debt securities, Fair Value	116,976	109,478
Commercial mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	58,485	48,299
Debt securities, Gross Unrealized Gains	4	16
Debt securities, Gross Unrealized Losses	(2,091)	(686)
Debt securities, Fair Value	$ 56,398	47,629
Equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity securities, Amortized Cost		847
Equity securities, Gross Unrealized Gains		24
Equity securities, Gross Unrealized Losses		(29)
Equity securities, fair value		$ 842

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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